Before an upgrade:
1) Remember to make backup/export files before an upgrade and save them on another storage device;
2) Make sure the device will not lose power during upgrade process;
3) Device has enough free storage space for all RouterOS packages to be downloaded.

To upgrade, click "Check for updates" at /system package in your RouterOS configuration interface, or head to our download page: http://www.mikrotik.com/download

If you experience version related issues, then please send supout file from your router to support@mikrotik.com. File must be generated while router is not working as suspected or after some problem has appeared on device

skullzaflare: see viewtopic.php?f=21&t=128915
Please, note that downgrading to previous RouterOS versions (below 6.41) will not restore "master-port" configuration, so use backups to restore configuration on downgrade.

M33 (mmips) as CAPSMAN, mix of mipsbe devices as CAPS.
Upgrade of M33 from 6.40.7 to 6.40.8 with no problems but CAPS have not connected to CAPSMAN.
They have not been upgraded automatically to "current" version as CAPSMAN configuration is set to.
After manual upgrade and restart they have connected imediatelly. All CAPS have access to Internet.

Unfortunately we can not backport any fixes to older versions. In order to get these updates you will need to upgrade above 6.40.x. All the fixes which are backportable and are tested - are included in bugfix versions. You simply will need at some point upgrade to the new bridge implementation and learn how to use it.

Thanks,will report any findings we find migrating from v6.40.7-8 though a couple of customers were unimpressed when we told them we'd have to sit and patch all the equipment again.
Have started testing for the inevitable new bridge implementation , but have found some things a bit hard to find.

Will probably take a bit of time to get accustomed to the "new" way of doing things.

Last edited by djdrastic on Wed Apr 25, 2018 9:28 pm, edited 1 time in total.

You are always welcome to ask questions through support@mikrotik.com e-mail. If you find out something that seems to be a bug, then report it through the same e-mail. Same rules apply to any version and any other process besides bridge. If something is working on version X and is not working on version Y, then report such problem to us.

I updated to v6.40.8 this morning. I was working in Winbox this evening and kept getting disconnected. I have updated to the newest Winbox release and am still getting disconnected. There is no log entry as to why.

I updated to v6.40.8 this morning. I was working in Winbox this evening and kept getting disconnected. I have updated to the newest Winbox release and am still getting disconnected. There is no log entry as to why.

Hi, I have a problem on my wireless after update from 6.40.7 to 6.40.8 few days ago on my hAP ac device.
Sometimes all the wireless devices will be disconnected few seconds and then reconnect to the router and this problem happen quite frequently.
Sometimes it could happen few times per hour.
I see in the router log showing 00:00:00:00:00:00@wlan1: disconnected, unicast key exchange timeout and wlan1 00:00:00:00:00:00 was WDS master every time the disconnect happen.
Should I downgrade it to 6.40.7 or need some config changes?
Thank you.

I have just updated rb750GR3 with dude package installed from 6.40.5 to 6.40.8 which resulted into bootloop without any beep.
Netinstalled 6.40.8 and imported rsc file generated by 6.40.5 before.
Only about 1/3 of the config was imported on the first run, so the rest needed to be copy-pasted into terminal window afterwards. It was not signalized anyhow.
After that, first minutes of run looks good...

So be prepaired when you decide to do the same!

edit: not so good... the ntp client looks to be not working and the environment of the scripts (variables) are not created/populated.

I was with my cloud core router restarting every day saying kernel failure,
I decided to update to last version and it did not solve, I decided to buy another cloud core and it continues with the same problem says:

I use The DUDE 6.40.8 client with wine. The server: 6.40.8 on RouterBOARD 750G r3
While changing the name of any my functions the client disconnects from the server with message: server likely crashed
and connects again
When I look into RouterBOARD 750G r3 log: Dude server started

I have upgraded on of my x86 edge bgp peering routers from 6.37.4 to 6.40.8,

I have noticed the the following issues on ipv6 bgp sessions that sessions with MD5 Keys do not establish a connection but the ipv4 sessions do.

I then upgraded the same router to 6.42.1 and the ipv6 bgp sessions with md5 keys work again.

has someone else seen these issues?

I have seen BGP issues even without MD5 in IPv4. In fact the reason I stopped upgrading ROS was exactly that as BGP for me is a must. BGP routes sometimes would get updated but would expire after a couple of minutes and some other times would not. Latest current ROS versions seem to fix this issue. Bugfix versions had the same problem for me.

i am curious which and when next bugfix version with "new bridge implementation" will be.....6.42.x ?
"new bridge implementation" was a big change. so going from 6.40.8 to new bugfix (>6.41.x ) dont know if it will be "a walk in the park" for some users.

i am curious which and when next bugfix version with "new bridge implementation" will be.....6.42.x ?
"new bridge implementation" was a big change. so going from 6.40.8 to new bugfix (>6.41.x ) dont know if it will be "a walk in the park" for some users.

I'm afraid MT won't care about that much, since they introduced that kind of change in rather minor version change (not on 7.0.0, but on next 6.x.x-current). So the best would be to leave 6.40.x be 'like old one' and keep develop 6.42+.

Nothing personal, still under impression from this "good" move as new killer-feature in next current release :)